Twisted wire producing apparatus and twisted wire producing method

ABSTRACT

A twisted wire producing apparatus includes an electric wire twisting unit that twists two electric wires, a controller that controls the electric wire twisting unit, and a tension adding part that adds tension to the two electric wires. The electric wire twisting unit includes a one end chuck part, the other end chuck part, and chuck rotating parts for rotating the one end chuck part and/or the other end chuck part under control of the controller. The other end chuck part includes a base, a chuck main body, twist prevention parts, and a wire length difference absorbing part. The wire length difference absorbing part includes an inter-electric wire inserting part which is movable in a direction perpendicular to the electric wires extending direction.

CROSS REFERENCE TO RELATED APPLICATION

This application is based on Japanese Patent Application No. 2017-005620filed on Jan. 17, 2017, the contents of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION 1. Technical Field

The present invention relates to a twisted wire producing apparatus forproducing a twisted wire having a twisted section and terminal untwistedsections continuing at opposite sides of the twisted section by twistingtwo electric wires, and a twisted wire producing method using the same.

2. Background Art

For example, to electrically connect between devices mounted on avehicle, a wire harness is routed in the vehicle. The wire harnessincludes a plurality of sub-harnesses. The wire harness of thisconfiguration is produced by combining the sub-harnesses to fit adesired circuit pattern. One of the sub-harnesses includes a twistedpair wire (a twisted wire).

In FIGS. 28A and 28B, a twisted wire 102 having a twisted section 107 isproduced by twisting two electric wires 101. As an apparatus forproducing this twisted wire 102, one disclosed in, for example,JP-A-2008-277032 is known. A twisted wire producing apparatus (anelectric wire twisting apparatus) of JP-A-2008-277032 includes a workstation, a holder that holds one end of each of two electric wires onthis work station, a motor that rotates the holder around an axis, apair of rotary holders formed by mutually juxtaposing single coreholders, each of which holds the other end of one of the electric wiresto be rotatable around an axis, a movable holder that is provided to bemovable along the axis, a driver that moves the movable holder along theaxis, and a controller that controls a movement speed, and the like ofthe movable holder.

Meanwhile, the following problems regarding the production of thetwisted wire are pointed out in JP-A-2012-28199 (see FIG. 7). That is,as illustrated in FIG. 29, in a producing apparatus including a commonclamp 202 that fixes one end of each of two electric wires 201, clamps203 that individually fix the other ends of the two electric wires 201,a device (not illustrated) that applies back tension from the commonclamp 202 side, and a rotor 204 that is arranged between the commonclamp 202 and each clamp 203, with regard to the production of thetwisted wire, if the two electric wires 201 have a variation within adimensional tolerance (in a state in which there is a wire lengthdifference by which one thereof is longer than the other), a problemthat the long electric wire 201 is twisted to be in a slightly loosestate is pointed out.

In the related art, when the long electric wire 201 is twisted in aslightly loose state, the variation (the wire length difference) isabsorbed by the twisted section although particularly not illustrated.

When this absorption is made, accuracy of a twist pitch is naturallyreduced, and thus the twisted section is formed in an uneven state. Theunevenly formed state has a problem that a quality needs to beguaranteed by performing, for instance, measurement of an inter-wire gapand a characteristic impedance of the twisted section, and thus a highproduction cost is required.

The present invention was made in view of the above circumstances, andan object thereof is to provide a twisted wire producing apparatus and atwisted wire producing method capable of improving reliability of atwisted wire and contributing to reduction in cost.

SUMMARY OF THE INVENTION

(1) According to an aspect of the invention, a twisted wire producingapparatus for producing a twisted wire having a twisted section andterminal untwisted sections each continuing to corresponding one ofsides of the twisted section by twisting two electric wires. The twistedwire producing apparatus includes:

an electric wire twisting unit that performs twisting on the twoelectric wires;

a controller that controls the electric wire twisting unit; and

a tension adding part that adds tension to the two electric wires;

wherein the electric wire twisting unit includes a one end chuck partfor chucking one ends of the two electric wires, the other end chuckpart for chucking the other ends of the two electric wires, and chuckrotating parts for rotating the one end chuck part and/or the other endchuck part under control of the controller,

the other end chuck part includes:

-   -   a base;    -   a chuck main body provided at the base and configured to fix the        other ends of the two electric wires at prescribed positions;    -   twist prevention parts directly or indirectly provided at the        base corresponding to a boundary position between the twisted        section and the terminal untwisted section; and    -   a wire length difference absorbing part directly or indirectly        provided at the base to absorb a wire length difference        occurring at the two electric wires,

the wire length difference absorbing part includes an inter-electricwire inserting part stuck between electric wires of the two electricwires, and

the inter-electric wire inserting part is provided as a part that ismovable in a direction perpendicular to a direction in which the twoelectric wires extend, and is disposed corresponding to an intermediateposition between the twist prevention parts and the chuck main body.

(2) In the twisted wire producing apparatus of (1), the inter-electricwire inserting part is formed in a shape of a pin having a circularcross section and is formed as a replaceable component to matchabsorption amount of the wire length difference by replacing theinter-electric wire inserting part with the other inter-electric wireinserting part having a different diameter.

(3) In the twisted wire producing apparatus of (1) or (2), the other endchuck part further includes a terminal contact part for bringing tips ofterminal fittings provided on the two electric wires into contact witheach other at the same position.

(4) According to another aspect of the invention, a twisted wireproducing method for producing a twisted wire having a twisted sectionand terminal untwisted sections each continuing to corresponding one ofsides of the twisted section by twisting two electric wires. The twistedwire producing method includes:

twisting an electric wire;

performing pre-processes prior to the twisting process that includes:

-   -   chucking one ends of the two electric wires with a one end chuck        part;    -   chucking the other ends of the two electric wires with the other        end chuck part;    -   adding tension to the two electric wires with a tension adding        part; and    -   absorbing a wire length difference between the two electric        wires using at least the other end chuck part,

the wire length difference absorbing process is configured to absorb thewire length difference at a section between a boundary position betweenthe twisted section and the terminal untwisted section and a position atwhich the electric wires are chucked by the other end chuck part.

Functions of the present invention having the above features will bedescribed in detail in embodiments in the present specification, anddescription thereof will be omitted here.

According to the present invention described in (1), the twisted wireproducing apparatus is a twisted wire producing apparatus including thewire length difference absorbing part and so on. Thus, although avariation (a wire length difference) within a dimensional tolerancewithin which one of the two electric wires is longer than the other ispresent at the two electric wires, an effect that this variation can beabsorbed by the wire length difference absorbing part is exerted. As inthe present invention, if the wire length difference can be absorbed, aneffect that a state in which the twisted section is formed at thetwisted wire can be stabilized is exerted. According to the presentinvention, since the wire length difference absorbing part is arrangedat a position corresponding to the terminal untwisted section of thetwisted wire, no hindrance is caused in forming the twisted section. Asa result, an effect that the state in which the twisted section isformed can be further stabilized is exerted.

According to the present invention, since the state in which the twistedsection is formed can be stabilized, an effect that a quality can beguaranteed without performing measurement or the like of an inter-wiregap and a characteristic impedance is exerted. Therefore, according tothe present invention, an effect that a twisted wire producing apparatusthat has high reliability of the twisted wire and can contribute to areduction in cost can be provided is exerted.

According to the present invention described in (2), with regard to theinter-electric wire inserting part constituting the wire lengthdifference absorbing part, an effect that a better structure can beprovided is exerted.

According to the present invention described in (3), the other end chuckpart is configured to further include the terminal contact part. Thus,an effect that, after the tips of the terminal fittings come intocontact at the same position, the other ends of the two electric wirescan be chucked by the other end chuck part, and thus it can be easy todo work regarding setting of the two electric wires is exerted.

According to the present invention described in (4), the twisted wireproducing method is a method suitable to produce the twisted wire usinga twisted wire producing apparatus including a wire length differenceabsorbing part and so on. Thus, although a variation (a wire lengthdifference) within a dimensional tolerance within which one of the twoelectric wires is longer than the other is present at the two electricwires, an effect that this variation can be absorbed by the wire lengthdifference absorbing part is exerted. As in the present invention, ifthe wire length difference can be absorbed, an effect that a state inwhich the twisted section is formed at the twisted wire can bestabilized is exerted. According to the present invention, since thewire length difference absorbing part is arranged at a positioncorresponding to the terminal untwisted section of the twisted wire, nohindrance is caused in forming the twisted section. As a result, aneffect that the state in which the twisted section is formed can befurther stabilized is exerted.

According to the present invention, since the state in which the twistedsection is formed can be stabilized, an effect that a quality can beguaranteed without performing measurement or the like of an inter-wiregap and a characteristic impedance is exerted. Therefore, according tothe present invention, an effect that a twisted wire producing methodthat has high reliability of the twisted wire and can contribute to areduction in cost can be provided is exerted.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a twisted wire producing apparatus ofthe present invention.

FIG. 2A is a view illustrating a twisted wire of a state in which thereis no wire length difference.

FIG. 2B is a view illustrating a twisted wire of a state in which thereis a wire length difference.

FIG. 3A is a view illustrating two electric wires of a state in whichthere is no wire length difference.

FIG. 3B is a view illustrating two electric wires of a state in whichthere is a wire length difference.

FIG. 4 is an enlarged view of a lower portion in the twisted wireproducing apparatus of FIG. 1.

FIG. 5 is an enlarged view of key parts of FIG. 4.

FIG. 6 is an enlarged view of an electric wire elevating unit of FIG. 5.

FIG. 7 is an enlarged view of an electric wire twisting unit of FIG. 5.

FIG. 8 is an enlarged view of a sensor and a light shielding part in theelectric wire elevating unit of FIG. 1.

FIG. 9 is a perspective view of the sensor of FIG. 8.

FIG. 10 is an enlarged view of a one end chuck part and the other endchuck part.

FIG. 11 is an explanatory view relating to an operation of the electricwire elevating unit of FIG. 1.

FIGS. 12A and 12B are explanatory views relating to a process of hangingthe middles of the electric wires in a twisted wire producing method (inthe case of a long twisted wire) of the present invention.

FIGS. 13A and 13B are explanatory views relating to a process ofchucking one ends of the electric wires and a first electric wirehoisting process in the twisted wire producing method of the presentinvention.

FIGS. 14A and 14B are explanatory views relating to a second electricwire hoisting process, a process of chucking the other ends of theelectric wires, and a tension adding process in the twisted wireproducing method of the present invention.

FIGS. 15A and 15B are explanatory views relating to an electric wiretwisting process (twisting of the other end side) in the twisted wireproducing method of the present invention.

FIGS. 16A and 16B are explanatory views relating to an electric wiretwisting process (twisting toward a middle untwisted section) in thetwisted wire producing method of the present invention.

FIGS. 17A and 17B are explanatory views relating to an electric wiretwisting process (twisting of one end side) in the twisted wireproducing method of the present invention.

FIGS. 18A and 18B are explanatory views relating to a taping process anda removing process in the twisted wire producing method of the presentinvention.

FIGS. 19A and 19B are explanatory views relating to a process of hangingthe middles of the electric wires in a twisted wire producing method (inthe case of a short twisted wire) of the present invention.

FIGS. 20A to 20C are explanatory views relating to a process of chuckingone ends of the electric wires, a third electric wire hoisting process,a process of chucking the other ends of the electric wires, and atension adding process in the twisted wire producing method of thepresent invention.

FIGS. 21A to 21C are explanatory views relating to an electric wiretwisting process (twisting of the other end side and movement of amiddle untwisted section) in the twisted wire producing method of thepresent invention.

FIGS. 22A to 22C are explanatory views relating to an electric wiretwisting process (twisting toward the middle untwisted section andtwisting of one end side) in the twisted wire producing method of thepresent invention.

FIGS. 23A and 23B are explanatory views relating to a taping process anda removing process in the twisted wire producing method of the presentinvention.

FIG. 24 is an explanatory view relating to a process of chucking theother ends of the electric wires (a state in which there is a wirelength difference).

FIG. 25 is an explanatory view relating to a tension adding process (astate in which there is a wire length difference).

FIG. 26 is an explanatory view relating to an electric wire twistingprocess (a state in which there is a wire length difference).

FIG. 27 is an enlarged view of a one end chuck part becoming anotherexample.

FIG. 28A is an explanatory view relating to a state in which the twoelectric wires are lined up according to the related-art example

FIG. 28B is an explanatory view illustrating a twisted wire.

FIG. 29 is a view relating to description of a conventional example in astate in which the wire length difference occurs at the two electricwires.

DETAILED DESCRIPTION OF EMBODIMENTS

A twisted wire producing apparatus is an apparatus for producing atwisted wire having a twisted section and terminal untwisted sectionseach continuing to corresponding one of sides of the twisted section bytwisting two electric wires, and includes: an electric wire twistingunit having a wire length difference absorbing part; a controller forcontrolling the electric wire twisting unit; and a tension adding partfor adding tension to the two electric wires. The wire length differenceabsorbing part is formed at a portion that is arranged at a positioncorresponding to the terminal untwisted section of the twisted wire andabsorbs a wire length difference occurring at the two electric wires.Meanwhile, a twisted wire producing method is a method that includes aprocess of performing absorption of the wire length difference with thewire length difference absorbing part before twisting.

Embodiment

Hereinafter, an embodiment will be described with reference to thedrawings. FIG. 1 is a perspective view of a twisted wire producingapparatus of the present invention. FIGS. 2A and 2B are viewsillustrating a twisted wire, and FIGS. 3A and 3B are views illustratingtwo electric wires. FIG. 4 is an enlarged view of a lower portion in thetwisted wire producing apparatus of FIG. 1, and FIG. 5 is an enlargedview of key parts of FIG. 4. FIG. 6 is an enlarged view of an electricwire elevating unit of FIG. 5, and FIG. 7 is an enlarged view of anelectric wire twisting unit of FIG. 5. FIG. 8 is an enlarged view of asensor and a light shielding part in the electric wire elevating unit ofFIG. 1, and FIG. 9 is a perspective view of the sensor of FIG. 8. FIG.10 is an enlarged view of a one end chuck part and the other end chuckpart, and FIG. 11 is an explanatory view relating to an operation of theelectric wire elevating unit of FIG. 1.

FIGS. 12A to 18B are explanatory views relating to each process of atwisted wire producing method (in the case of a long twisted wire) ofthe present invention, and FIGS. 19A to 23B are explanatory viewsrelating to each process of a twisted wire producing method (in the caseof a short twisted wire) of the present invention. FIGS. 24 to 26 areexplanatory views relating to each process of a twisted wire producingmethod (in the case of a twisted wire having a wire length difference)of the present invention, and FIG. 27 is an enlarged view of the one endchuck part becoming another example.

Configuration of Twisted Wire Producing Apparatus 1

In FIG. 1, a twisted wire producing apparatus 1 is an apparatus forproducing a twisted wire 102 (see FIGS. 2A and 2B), and includes anelectric wire elevating unit 2, an electric wire twisting unit 3, acontroller 4 for controlling the entire apparatus, and a frame 5 forinstalling each of these units at a prescribed position of theapparatus. The twisted wire producing apparatus 1 also includes a wirelength difference absorbing part 66, a tension adding part 12, etc. thatare characteristic parts of the present invention. Hereinafter, eachconfiguration will be described.

Twisted Wire 102 and Two Electric Wires 101

In FIGS. 2A, 2B, 3A, and 3B, the twisted wire 102 has the sameconfiguration as a twisted wire 102 (an example of the related art) ofFIGS. 28A and 28B, and is produced by twisting two electric wires 101.

In the twisted wire 102 and the two electric wires 101, a referencenumeral 103 indicates one end, a reference numeral 104 indicates theother end, a reference numeral 105 indicates a middle, a referencenumeral 107 indicates a twisted section, a reference numeral 108indicates a terminal fitting, a reference numeral 110 indicates aterminal untwisted section close to one end, a reference numeral 111indicates a terminal untwisted section close to the other end, and areference numeral TP indicates taping. Although will be described withreference to other drawings, a U turn section 106 (see FIGS. 12A and12B) and a middle untwisted section 109 (see FIGS. 16A and 16B) occur ina producing process.

In FIGS. 2A, 2B, 3A, and 3B, it is illustrated that a variation within adimensional tolerance occurs and does not occur in the twisted wire 102and the two electric wires 101. In other words, it is illustrated thatone electric wire 101 has such a wire length difference as to be longerthan the other electric wire 101 by ΔL and does not have. The wirelength difference ΔL occurs at the side of the other end 104, but thisis an example. That is, the wire length difference ΔL may occur at theside of the one end 103, or both the one end 103 and the other end 104(properly set depending on the dimensional tolerance).

In the present invention, even when the variation (the wire lengthdifference ΔL) within the dimensional tolerance regarding production ofthe twisted wire 102 is present in the two electric wires 101, the longelectric wire 101 is devised not to be in a slightly loose state at aposition of the twisted section 107. This devisal is a feature of thepresent invention, and comes to be understood in the followingdescription.

Electric Wire Elevating Unit 2

In FIGS. 1, 4, 5, and 6, the electric wire elevating unit 2 is providedas a unit for hoisting the two electric wires 101 (see FIGS. 3A and 3B)and performing a descent after the twisted wire 102 (see FIGS. 2A, 2B,18A, and 18B) is produced. This electric wire elevating unit 2 includesan elevating part 6 that acts as a part for hoisting the two electricwires 101, an elevating guide part 7 for guiding the elevating part 6 ina vertical direction, and a high/low-speed elevating unit 8 forelevating the elevating part 6 at a high speed or at a low speed.

Elevating Part 6

In FIGS. 5 and 6, the elevating part 6 includes a main body 9, anelectric wire hanging part 10 provided for the main body 9, and anelectric wire pressing part 11 and a tension adding part 12 that areequally provided for the main body 9. In addition, the elevating part 6of the present embodiment includes a pair of option chuck parts 13 and apair of electric wire guards 14 that are provided for the main body 9.

Main Body 9 of Elevating Part

In FIG. 5, the main body 9 of the present embodiment is made up of twomembers up and down. To be specific, the main body 9 is made up of anupper main body 15 and a lower main body 16. The upper main body 15 andthe lower main body 16 are coupled via the tension adding part 12. Thetension adding part 12 will be described below, but it is a memberhaving elasticity in a vertical direction. The tension adding part 12 isone of characteristic parts of the present invention, and is provided toadd tension (add a tensile force) to the two electric wires 101.

The upper main body 15 and the lower main body 16 are formed such thatthe lower main body 16 is raised and lowered by the high/low-speedelevating unit 8 (to be described below) or the upper main body 15 isalso guided in a vertical direction by the elevating guide part 7 (to bedescribed below) in association with the raising/lowering.

Upper Main Body 15

In FIG. 6, the upper main body 15 has a front wall 17, a left wall 18, aright wall 19, and a rear wall 20, and is formed in an approximatelytubular shape. The electric wire hanging part 10 and the electric wirepressing part 11 are provided on a front surface of the front wall 17.The front wall 17 is formed in an asymmetrical shape in which a rightside thereof further extends in a rightward direction. A band plate-likeportion protruding downward is formed at the rightward extendingportion. The right option chuck part of the pair of option chuck parts13 and the right electric wire guard of the pair of electric wire guards14 are provided at the band plate-like portion.

The left wall 18 and the right wall 19 are fixed to a rear surface ofthe front wall 17 at a prescribed interval. A light shielding segment 32(to be described below) is provided below the left wall 18. The lightshielding segment 32 is disposed to correspond to positions of a pair ofsensors 33 (to be described below). The light shielding segment 32 andthe sensors 33 are provided as one configuration of the high/low-speedelevating unit 8 (to be described below) to detect an applied state oftension when the two electric wires 101 are hoisted (see FIGS. 14A and14B).

The rear wall 20 is fixed to the left wall 18 and the right wall 19. Aguide convex part 21, which is inserted into a guide concave part 25 ofthe elevating guide part 7 (to be described below) and is guided in avertical direction, is provided for this rear wall 20. The guide convexpart 21 is formed at a convex part.

Electric Wire Hanging Part 10

In FIGS. 6, 12A, and 12B, the electric wire hanging part 10 is formed asa part for hanging each of the U turn sections 106 formed in the middles105 of the two electric wires 101. In the present embodiment, theelectric wire hanging part 10 is formed in the shape of a circularroller, and is formed to be rotatable. A concave part 22 is formed roundthis electric wire hanging part 10. The concave part 22 is formed as apart for making the U turn sections 106 difficult to drop out.

Electric Wire Pressing Part 11

In FIG. 6, the electric wire pressing part 11 is provided as a part forpressing each of the U turn sections 106 from above after the U turnsections 106 (see FIGS. 12A and 12B) are hung not to intersect eachother at the concave part 22 of the electric wire hanging part 10 orcovering the concave part 22. The electric wire pressing part 11 isprovided as a part for preventing dropout and looseness of the electricwires during hoisting.

Lower Main Body 16

In FIGS. 5 and 6, the lower main body 16 is formed at a tabular part. Aleft upper portion of the lower main body 16 is coupled to a couplingarm 29 of the high/low-speed elevating unit 8 (to be described below).The lower main body 16 is formed to be able to be raised and lowered bythe coupling arm 29. The lower main body 16 is guided along theelevating guide part 7 (to be described below) in a vertical direction.A placing part 23, a light shielding part 31 (to be described below),the left option chuck part of the pair of option chuck parts 13, and theleft electric wire guard of the pair of electric wire guards 14 areprovided for this lower main body 16. The light shielding part 31 isdisposed at positions corresponding to the sensors 30 (to be describedbelow). The light shielding part 31 and the sensors 30 are provided asone configuration of the high/low-speed elevating unit 8 (to bedescribed below).

Placing Part 23

In FIG. 5, the placing part 23 is formed at a flaky portion that islaterally long and protrudes forward. The placing part 23 is formed tobe able to place and fix a lower end side of the tension adding part 12on an upper surface thereof.

Tension Adding Part 12

In FIGS. 5 and 6, the tension adding part 12 is a member having a springcontracted downward when a load is applied, and is formed such that alower end side thereof is fixed to the placing part 23 and an upper endthereof can be assembled to the upper main body 15. As described above,the tension adding part 12 is one of the characteristic parts of thepresent invention, and is provided as a part that can apply a “restoringforce” generated when contracted downward to the two electric wires 101.

Pair of Option Chuck Parts

In FIGS. 5 and 6, the pair of option chuck parts 13 are used when shortelectric wires that are not illustrated in the two drawings are twisted.The pair of option chuck parts 13 are formed as parts that can chuckupper ends of the short electric wires. The pair of option chuck parts13 are disposed at positions directly above one end and other end chuckparts 42 and 43 of the electric wire twisting unit 3 (to be describedbelow). The pair of option chuck parts 13 are arranged at positions atwhich the short electric wires can be hoisted at straight upper sides(not in an U-turned state).

If there is an apparatus that does not require the twisting of the shortelectric wires, the pair of option chuck parts 13 may not be provided(the pair of electric wire guards 14 to be described below may not beprovided as well).

Pair of Electric Wire Guards 14

In FIGS. 5 and 6, the pair of electric wire guards 14 are provided suchthat, when the twisted wire 102 (see FIGS. 2A and 2B) is produced, thetwo electric wires 101 (see FIGS. 12A to 18B) are not in contact withthe pair of option chuck parts 13.

Elevating Guide Part 7

In FIGS. 1 and 4 to 8, the elevating guide part 7 is a rod-like memberthat extends straight in a vertical direction, and is formed with afixture for the frame 5 at a lower end side thereof. The elevating guidepart 7 is formed to have a height dimension that is equal to or morethan at least half of the full length of the produced twisted wire 102(see FIGS. 2A, 2B, 18A, and 18B). The elevating guide part 7 is formedto be able to guide (raise or lower) the upper main body 15 in avertical direction. To be specific, the elevating guide part 7 is formedin a shape having the recessed (groove-like) guide concave part 25. Theguide concave part 25 is disposed and formed on the front surface of theelevating guide part 7.

The sensors 30 (to be described below) are provided on a right surfaceof the elevating guide part 7. The sensors 30 are adapted to detect araised position and a lowered position of the elevating part 6, and arearranged in a plurality of places at a prescribed interval.

High/Low-Speed Elevating Unit 8

In FIGS. 1 and 4 to 6, as described above, the high/low-speed elevatingunit 8 is provided for the twisted wire producing apparatus 1 toraise/lower the elevating part 6 at a high or low speed. As regards thetwisted wire producing apparatus 1, it is characterized in that itincludes the high/low-speed elevating unit 8, and thus is not configuredto merely hoist the two electric wires 101 (see FIGS. 12A, 12B, 18A, and18B). The high/low-speed elevating unit 8 is controlled by thecontroller 4 (to be described below).

The high/low-speed elevating unit 8 of the present embodiment isconfigured to be able to be raised and lowered using an air cylinder (itis not limited thereto. For example, the high/low-speed elevating unit 8may be configured to be raised and lowered by a motor or the like. Inthe present embodiment, the high/low-speed elevating unit 8 aims atrequiring no cost.). To be specific, the high/low-speed elevating unit 8includes an elevating cylinder 27, an air feeder 28 for feeding air tothis elevating cylinder 27, a coupling arm 29 interposed between theelevating cylinder 27 and the elevating part 6, the sensors 30 providedin a plurality of places of the elevating guide part 7, the lightshielding part 31 provided for the elevating part 6, the light shieldingsegment 32 provided for the elevating part 6, and sensors 33 providedfor the coupling arm 29.

Elevating Cylinder 27

In FIGS. 1 and 4 to 6, the elevating cylinder 27 is a well-known aircylinder, and adopts a cylinder having a length required to produce thetwisted wire 102 (see FIGS. 12A, 12B, 18A, and 18B). In the presentembodiment, the elevating cylinder 27 adopts a long cylinder, and isarranged in a state in which it extends parallel to the elevating guidepart 7 in a vertical direction.

Air Feeder 28

In FIGS. 1 and 4, the air feeder 28 is arranged in a box 34 fixed to theframe 5 as an example. The air feeder 28 is configured to have, forinstance, a plurality of parts illustrated in FIG. 11.

In FIG. 11, to be specific, the air feeder 28 has a source pressuregenerator part 28 a for generating a “source pressure,” a high-pressureair regulator part 28 b that is connected to the source pressuregenerator part 28 a and functions as a “high-pressure air regulator,” alow-pressure air regulator part 28 c that is connected to the sourcepressure generator part 28 a and functions as a “low-pressure airregulator,” an air pressure switching electromagnetic valve part 28 dthat is connected to the high- and low-pressure air regulator parts 28 band 28 c and functions as an “air pressure switching electromagneticvalve,” and a raising/lowering switching electromagnetic valve part 28 ethat is connected to the air pressure switching electromagnetic valvepart 28 d and functions as a “raising/lowering switching electromagneticvalve.” That is, the air feeder 28 can be configured to raise/lower theelevating cylinder 27 with high-pressure air or low-pressure air.

As an example, a power supply 35 for supplying power, a main body 52 ofthe controller 4 (to be described below), etc. are also arranged in thebox 34 in which the air feeder 28 as described above is arranged.

Coupling Arm 29

In FIGS. 5 and 6, the coupling arm 29 is an L-shaped band plate member,and one end thereof is fixed to a telescopic part of the elevatingcylinder 27. The other end of the coupling arm 29 is fixed to the lowermain body 16 of the elevating part 6. This coupling arm 29 is formed tobe able to raise/lower the lower main body 16 along with expansion andcontraction (vertical movement) of the elevating cylinder 27.

When the lower main body 16 is raised and lowered, the upper main body15 is also raised and lowered, and therefore the electric wire hangingpart 10 provided for the upper main body 15 is also raised and lowered.Since the electric wire hanging part 10 is a part for hanging the U turnsections 106 (see FIGS. 12A and 12B) occurring at the two electric wires101 (see FIGS. 12A and 12B), when the coupling arm 29 is raised, the twoelectric wires 101 are hoisted.

Sensors 30

In FIG. 1, the sensors 30 are provided in a plurality of places of theright surface of the elevating guide part 7 at a prescribed interval.These sensors 30 are provided to detect a position of the elevating part6.

In FIGS. 8 and 9, a sensor main body 37 connected to the controller 4(see FIG. 4) (to be described below) via signal lines 36 is provided foreach of the sensors 30. A light emitting part 38 emitting light and alight receiving part 39 receiving the light from the light emitting part38 are provided for the sensor main body 37. A space 40 through whichthe light shielding part 31 passes is formed between the light emittingpart 38 and the light receiving part 39. A well-known photosensor isadopted as the sensor 30 of the present embodiment.

Light Shielding Part 31

In FIGS. 6 and 8, like the sensors 30, the light shielding part 31 isprovided to detect the position of the elevating part 6. The lightshielding part 31 is formed at a plate-like portion that can block thelight from the light emitting part 38 in the sensor 30. The lightshielding part 31 is disposed to pass through the space 40 of the sensormain body 37 when the elevating part 6 is raised and lowered.

Light Shielding Segment 32

In FIG. 6, the light shielding segment 32 is provided below the leftwall 18 of the upper main body 15 in the elevating part 6. The lightshielding segment 32 is provided to detect a position of the upper mainbody 15 that is spring-biased by the tension adding part 12. When thelight shielding segment 32 is located between the pair of upper andlower sensors 33, it is determined in the present embodiment thatadequate tension is applied to the two electric wires 101 (see FIGS.12A, 12B, 18A, and 18B).

Sensors 33

In FIG. 6, the sensors 33 are arranged on the coupling arm 29 via amounting part 41. The sensors 33 are arranged to vertically become apair at a prescribed interval. A light emitting part emitting light anda light receiving part receiving the light from the light emitting partare provided for each of the pair of sensors 33. A space through whichthe light shielding segment 32 passes is formed in each of the sensors33. A well-known photosensor is adopted as the sensor 33 of the presentembodiment.

Electric Wire Twisting Unit 3

In FIGS. 1, 4 and 5, the electric wire twisting unit 3 is provided to bearranged parallel to the electric wire elevating unit 2 and to chuck andtwist the two electric wires 101 (see FIGS. 3A, 3B, and 12A to 18B).This electric wire twisting unit 3 includes the one end chuck part 42,the other end chuck part 43, same-direction rotating parts (chuckrotating parts) 44, and chuck-vertical position changing unit 45.

One End Chuck Part 42 and Other End Chuck Part 43

In FIGS. 5 and 7, the one end chuck part 42 is configured to be able toremovably chuck one ends 103 of the two electric wires 101 (see FIGS.3A, 3B, and 12A to 18B). Likewise, the other end chuck part 43 is alsoconfigured to be able to removably chuck the other ends 104 of the twoelectric wires 101. The one end chuck part 42 and the other end chuckpart 43 have a similar configuration and structure as illustrated.However, in the present embodiment, they are different in that a wirelength difference absorbing part 66 that is one of the characteristicparts of the present invention is provided for the other end chuck part43 (they are not limited thereto. That is, both have the sameconfiguration and structure as illustrated in FIG. 27.) Hereinafter, theone end chuck part 42 and the other end chuck part 43 will be describedin detail with reference to FIG. 10.

Details of One End Chuck Part 42

In FIG. 10, the one end chuck part 42 includes a base 61, a terminalcontact part 62, a chuck main body 63, a block-shaped part 64, and twistprevention parts 65. As described above, the one end chuck part 42 ofthis configuration is configured to chuck the one ends 103 of the twoelectric wires 101 (see FIGS. 3A and 3B), and to be able to form theterminal untwisted section 110 of the one end side of the twisted wire102 (see FIGS. 2A and 2B) after being twisted.

The base 61 has a first base 61 a, one end of which is mounted on arotary shaft 47 (to be described below) of the same-direction rotatingparts 44 (see FIG. 7), and a second base 61 b that is connected to theother end of the first base 61 a, and the entire base 61 is formed in anL shape as illustrated. The second base 61 b and the first base 61 a areformed in long and short band plate shapes in the present embodiment.

The terminal contact part 62 is formed as a part that brings (can bring)tips of the terminal fittings 108 provided for the two electric wires101 (see FIGS. 3A and 3B) into contact at the same position. That is,the terminal contact part 62 is formed as a positioning part. Since theterminal contact part 62 exposes a tip face of the rotary shaft 47 (tobe described below) from the first base 61 a in the present embodiment,the terminal contact part 62 is formed along with this tip surface.

The chuck main body 63 is a part for actually chucking the one ends 103of the two electric wires 101 (see FIGS. 3A and 3B), and is formed to beable to removably hold the two electric wires 101 by pinching in thepresent embodiment. The chuck main body 63 is formed to be able tomaintain the holding even in a state in which tension (a tensile force)to be described below is applied to the two electric wires 101. Aconfiguration and structure of the chuck main body 63 are not limited tothose illustrated herein. For example, the chuck main body 63 may have aconfiguration that combines a well-known toggle clamp, and the like.

The block-shaped part 64 is formed in a shape that becomes, forinstance, a cuboid as illustrated (the shape is an example). Theblock-shaped part 64 is formed at a portion where a rear side thereof isfixed and integrated to a position of an upper end of the second base 61b. The twist prevention parts 65 are provided at the rear side of theblock-shaped part 64.

The twist prevention parts 65 are arranged at a position of an upper endof the second base 61 b via the block-shaped part 64. The twistprevention parts 65 are arranged corresponding on a boundary positionbetween the twisted section 107 and the terminal untwisted section 110of the one end side in the twisted wire 102 (see FIGS. 2A and 2B). Asthe twist prevention parts 65 of the present embodiment, a pair of pinsarranged side by side are adopted. The pair of pins are arranged at suchan interval as to insert the two electric wires 101 (see FIGS. 3A and3B). The twist prevention parts 65 are not limited to the presentembodiment, and may be directly arranged on the second base 61 b.

Details of Other End Chuck Part 43

In FIG. 10, the other end chuck part 43 includes a base 61, a terminalcontact part 62, a chuck main body 63, and a wire length differenceabsorbing part 66. The other end chuck part 43 of this configuration isconfigured to chuck the other ends 104 of the two electric wires 101(see FIGS. 3A, 3B, and 24), and to be able to form the terminaluntwisted section 111 of the other end side of the twisted wire 102 (seeFIGS. 2A and 2B) after being twisted.

The base 61, the terminal contact part 62, and the chuck main body 63are adopted in the same way as the one end chuck part 42. In the otherend chuck part 43, the other ends 104 of the two electric wires 101 (seeFIGS. 3A, 3B, and 24) are chucked with regard to the chuck main body 63.

Wire Length Difference Absorbing Part 66 of Other End Chuck Part 43

In FIGS. 10 and 24, the wire length difference absorbing part 66 is oneof the characteristic parts of the present invention, and includes ablock-shaped part 64, a block rotary shaft part 67, twist preventionparts 65, and an inter-electric wire inserting part 68.

The block-shaped part 64 is formed in the same cuboidal shape as in theone end chuck part 42 (the shape is an example). In the other end chuckpart 43, this block-shaped part 64 is mounted in a movable state asdescribed below without being integrally fixed to the second base 61 b.The twist prevention parts 65 are provided at a front surface side ofthe block-shaped part 64 at the same position as in the one end chuckpart 42.

The block rotary shaft part 67 is a part for making it possible to movethe inter-electric wire inserting part 68 (to be described below) in adirection perpendicular to extending directions of the two electricwires 101 (see FIGS. 3A, 3B, and 24), and is formed at a portion thatmakes it possible to move the block-shaped part 64 in a direction of anarrow in the drawing in the present embodiment (in other words, formedat a portion that makes movement possible in a rotational direction toswing). The movement of the block-shaped part 64 occurs when a forceacts on the inter-electric wire inserting part 68 (to be describedbelow).

The inter-electric wire inserting part 68 is formed as a part that isinserted between electric wires of the two electric wires 101 (see FIGS.3A, 3B, and 24). In the present embodiment, the inter-electric wireinserting part 68 is formed in the shape of a pin having a circularcross section. This inter-electric wire inserting part 68 is formed as areplaceable part that can change a diameter of the pin depending onabsorption of the wire length difference ΔL in the two electric wires101. The inter-electric wire inserting part 68 is provided to protrudefrom a position of a lower end on a surface of the block-shaped part 64.

The inter-electric wire inserting part 68 and the twist prevention parts65 are provided for the block-shaped part 64, and thus naturally becomeparts that are movable in the direction of the arrow in the figure.

The twist prevention parts 65 of the other end chuck part 43 arearranged corresponding on a boundary position between the twistedsection 107 and the terminal untwisted section 111 of the other end sidein the twisted wire 102 (see FIGS. 2A and 2B). As the twist preventionparts 65 of the present embodiment, a pair of pins arranged side by sideare adopted. The pair of pins are arranged at such an interval as toinsert the two electric wires 101 (see FIGS. 3A, 3B, and 24). The twistprevention parts 65 are not limited to the present embodiment, and maybe directly arranged at the second base 61 b.

Same-Direction Rotating Parts (Chuck Rotating Parts) 44

In FIGS. 5 and 7, the same-direction rotating parts 44 are configured tobe able to rotate the one end chuck part 42 and the other end chuck part43 at different timings in the same direction. The different timingsmean that rotations, such as rotating and stopping the other end chuckpart 43 first and rotating the one end chuck part 42 in turn, are notsynchronized. The same-direction rotating parts 44 include a pair ofmotors 46 that are controlled by the controller 4 (to be describedbelow), a pair of rotary shafts 47 that are rotated by the pair ofmotors 46, and a pair of motor fixing parts 48 for fixing the pair ofmotors 46. In the present embodiment, with regard to the pair of motorfixing parts 48, the left motor fixing part is fixed in a stationarystate, and the right motor fixing part is fixed to be movable using thechuck-vertical position changing unit 45 in a vertical direction.

Chuck-Vertical Position Changing Unit 45

In FIGS. 5 and 7, the chuck-vertical position changing unit 45 isconfigured to be able to change positions of the one end chuck part 42and the other end chuck part 43 in a vertical direction. In the case ofthe present embodiment, it is assumed that a structure is adopted inwhich the right motor 46 moves downward, thereby changing the twopositions in the vertical direction. When the configuration andstructure are described more concretely, the chuck-vertical positionchanging unit 45 includes a lowering cylinder 49, an air feeder 50 forfeeding air to the lowering cylinder 49, a slider rail 51 extending in avertical direction, and a guide convex part (reference numeral isomitted) that is provided for the right motor fixing part 48 and isguided by the slider rail 51. As an example, the air feeder 50 isarranged in the box 34. The slider rail 51 is fixed to the frame 5. Thechuck-vertical position changing unit 45 is controlled by the controller4 (to be described below).

Controller 4

In FIGS. 1 and 4, the controller 4 is provided to control operations ofthe electric wire elevating unit 2 and the electric wire twisting unit3. As an example, the controller 4 includes a main body 52 that isarranged in the box 34, and an operating part 53 that is fixed to, forinstance, a right side of the frame 5 and is operated by a worker. Themain body 52 includes a well-known PLC, and so on. The operating part 53is configured by, for example, touch panel. Various data required toproduce the twisted wire 102 (see FIGS. 2A, 2B, 18A, and 18B) are storedin a storage part of the main body 52. As the operating part 53, anypart is adopted as long as numerical values can be input.

Method of Producing Long Twisted Wire 102 (No Difference in Wire Length)

A producing process adopted in the twisted wire producing apparatus 1 asdescribed above includes a process of hanging the middles of theelectric wires, a process of chucking one ends of the electric wires, afirst electric wire hoisting process, a second electric wire hoistingprocess, a process of chucking the other ends of the electric wires, atension adding process, a wire length difference absorbing process, anelectric wire twisting process, a taping process, and a removing process(wherein the processes are an example. The reason is that the processesare somewhat different from processes provided in a method of producinga short twisted wire 102 (to be described below)).

In producing process as described above, based on the electric wiretwisting process, the processes earlier than the electric wire twistingprocess become pre-processes described. The processes later than theelectric wire twisting process becomes subsequent processes.

The following description with reference to FIGS. 12A to 18B is anexample of the case in which the wire length difference ΔL does notoccur at the two electric wires 101 (see FIGS. 3A and 3B), and thusmeans production as if the wire length difference absorbing process isnot performed. The wire length difference absorbing process will bedescribed below (see FIGS. 24 to 26).

Each process when there is no wire length difference will be describedwith reference to FIGS. 12A to 18B (as well as with reference to FIGS. 1to 11 as needed). Here, the apparatus is operated by operation of theoperating part 53 from the worker, and details of the operation will beomitted.

Process of Hanging the Middles of the Electric Wires

In the process of hanging the middles of the electric wires illustratedin FIGS. 12A and 12B, work of ejecting the two long electric wires 101from, for instance, a part rack (an electric wire stock rack) around aworker, and work of hanging the U turn sections 106 of the two electricwires 101 on the electric wire hanging part 10 are performed.

In the work of hanging the electric wire hanging part 10, since the twoelectric wires 101 are long, the U turn sections 106 are not formed inthe middles of the two electric wires 101, but they are bent and formedclose to the one ends 103 in a U shape.

The two electric wires 101 are hung on the electric wire hanging part 10such that the U turn sections 106 do not intersect each other (not tooverlap each other in the vertical direction). This is because, when theU turn sections 106 become an intersected state (a state in which theelectric wires intersect), a twist pitch (an electric wire pitch) ischanged during twisting.

After the U turn sections 106 are hung on the electric wire hanging part10, work of pressing the U turn sections 106 with the electric wirepressing part 11 is performed (the electric wire pressing part 11 has ahinge portion, and a state of the electric wire pressing part 11 isturned down from an L shape and turned horizontally. Thereby, the U turnsections 106 can be pressed from above.

A central line in a longitudinal direction of the paper in FIGS. 12A and12B indicates an axis when the electric wire hanging part 10 is raised(hoisted) or lowered, and schematically denotes the elevating guide part7. In addition to this, central lines in a transverse direction of thepaper indicates positions corresponding to a “first prescribed position”and a “second prescribed position (a position of a desired hoistingheight)” used in the following description. These positions will bedescribed in the following processes. In addition to these positions, aposition of the electric wire hanging part 10 illustrated in FIGS. 12Aand 12B is defined to be an “initial position” in the presentembodiment.

Process of Chucking One Ends of the Electric Wires

In the process of chucking one ends of the electric wires illustrated inFIG. 13A, work of chucking one ends 103 of the two electric wires 101with the one end chuck part 42 is performed. Although will be understoodin the following description, a range corresponding to the one end chuckpart 42, particularly a range becoming the vicinity of an electric wirechucking position, becomes a range in which twisting (to be describedbelow) is not performed.

First Electric Wire Hoisting Process

In the first electric wire hoisting process illustrated in FIGS. 13A and13B, the high/low-speed elevating unit 8 is operated to raise theposition of the electric wire hanging part 10 from the “initialposition” to the “first prescribed position” above the initial positionat a stroke (in the case of the long electric wires 101, when theelectric wire hanging part is slowly raised, a time is required as much.Thus, the electric wire hanging part is raised in a short time, that is,at a high speed, and thereby the time is shortened). With regard to theraising at a high speed, the air pressure switching electromagneticvalve part 28 d is set to a high air pressure by control (instruction)of the main body 52 of the controller. The raising/lowering switchingelectromagnetic valve part 28 e is set to the raising. The raising ofthe electric wire hanging part 10 is initiated by these parts. That is,the hoisting of the two electric wires 101 is initiated.

In the first electric wire hoisting process, with the raising of theelectric wire hanging part 10, the positions of the U turn sections 106are changed. When a worker does work of placing a hand at a leftelectric wire portion (an electric wire portion close to the other ends104) from the U turn sections 106, flapping of the two electric wires101 associated with the raising can be suppressed.

When the electric wire hanging part 10 reaches the “first prescribedposition,” the electric wire hanging part 10 is raised close to (justbefore) the desired hoisting height (the “first prescribed position” isa position close to the desired hoisting height. In the presentembodiment, the first prescribed position is also a position of thesensor 30 approximately in the middle of the elevating guide part 7.).

Second Electric Wire Hoisting Process

In the second electric wire hoisting process illustrated in FIGS. 13Band 14A, the high/low-speed elevating unit 8 is operated to slowly raisethe position of the electric wire hanging part 10 from the “firstprescribed position” to the “second prescribed position (the position ofthe desired hoisting height)” slightly above the first prescribedposition (the electric wire hanging part is slowly raised at a lowspeed, which aims at preventing a tensile force from being abruptlyapplied). With regard to the raising at a low speed, when thecorresponding sensor 30 is arranged corresponding to the “firstprescribed position,” and the light shielding part 31 passes throughthis sensor 30, a signal is sent to the controller main body 52. Whenthe air pressure switching electromagnetic valve part 28 d is switchedto a low air pressure by the control (the instruction) of the controllermain body 52, the raising of the electric wire hanging part 10 at a lowspeed is initiated. That is, the raising is switched such that thehoisting of the two electric wires 101 is performed by a remainingslight amount up to “the position of the desired hoisting height.”

In FIG. 14A, when the electric wire hanging part 10 reaches the “secondprescribed position,” the electric wire hanging part 10 is raised to theposition of the desired hoisting height. In the present embodiment, whena signal is sent from the sensor 30 to the controller main body 52 atthe “first prescribed position,” a timer is operated at the controllermain body 52, the electric wire hanging part 10 is slowly raised for aprescribed time (several seconds), and then a control method in whichthe electric wire hanging part 10 is exactly stopped at the position ofthe desired hoisting height is adopted (the control method is anexample).

Process of Chucking the Other Ends of the Electric Wires

In the process of chucking the other ends of the electric wiresillustrated in FIG. 14B, work of chucking the other ends 104 of the twoelectric wires 101 with the other end chuck part 43 is performed. Atthis time, the other ends 104 of the two electric wires 101 becomes astate as illustrated in FIG. 24. That is, the two terminal fittings 108are disposed at the same position by the terminal contact part 62, andthe two electric wires 101 become a state in which they are tucked andheld in the chuck main body 63 in the vicinity of the two terminalfittings 108. The two electric wires 101 become a state in which theyare stuck between the twist prevention parts 65 (the pair of pinsarranged side by side), and the inter-electric wire inserting part 68becomes a state in which it is stuck between the electric wires of thetwo electric wires 101.

The process of chucking the other ends of the electric wires may beconfigured to be performed prior to the aforementioned first and secondelectric wire hoisting processes.

The positioning of the two terminal fittings 108 as described above isalso performed in the process of chucking one ends of the electricwires.

Tension Adding Process

In FIG. 14B, when the position of the electric wire hanging part 10 israised to the “second prescribed position (the position of the desiredhoisting height,” a “restoring force” generated by downward contractionof the tension adding part 12 is applied to the two electric wires 101at this time. That is, excessive tension is applied.

In the present embodiment, the tension adding process is a process inwhich tension is automatically added.

Electric Wire Twisting Process

In the electric wire twisting process illustrated in FIG. 15A, first tosixth processes below are performed in turn.

First, in a first process, the other end chuck part 43 is rotated, forinstance, in a direction of an arrow by the left same-direction rotatingpart 44. Next, in a second process, as illustrated in FIG. 15B, theother end chuck part 43 is rotated only several times in the oppositedirection of the above (so-called untwisting is performed.). The twistedsection 107 is formed at the left side of the electric wire hanging part10 by these two processes. Next, in a third process, the chuck-verticalposition changing unit 45 is operated to slightly change the positionsof the electric wire hanging part 10 and the one end chuck part 42 in adownward direction as illustrated in FIG. 16A. At this time, thepositions of the U turn sections 106 hung on the electric wire hangingpart 10 are displaced. In other words, a position of the middleuntwisted section 109 in which no twist may occur due to contact withthe electric wire hanging part 10 is displaced in a clockwise direction.

Next, in a fourth process, as illustrated in FIG. 16B, the one end chuckpart 42 is rotated in a direction of an arrow by the rightsame-direction rotating part 44. Next, in a fifth process, asillustrated in FIG. 17A, the one end chuck part 42 is rotated onlyseveral times in the opposite direction of the above (so-calleduntwisting is performed.). The twisted section 107 is also formed at theright side of the electric wire hanging part 10 by these two processes.Finally, in a sixth process, the positions of the electric wire hangingpart 10 and the one end chuck part 42 which are changed in a downwarddirection are restored. Due to this process, the twisted section 107 isdisposed at both sides of the electric wire hanging part 10 at a uniformlength.

Taping Process

In FIG. 18A, work for taping TP is performed in this process. The tapingTP is formed by winding a tape 54 at ends of the twisted section 107around the one end chuck part 42 and the other end chuck part 43. Thetaping TP is carried out for anti-fraying.

Removing Process

In the removing process illustrated in FIG. 18B, the high/low-speedelevating unit 8 is operated to return the position of the electric wirehanging part 10 from the “second prescribed position (position of thedesired hoisting height” to the “initial position.” Work of removing oneend 103 and the other end 104 of the twisted wire 102 from the one endchuck part 42 and the other end chuck part 43 is also performed. Thesequential production is completed by the removal of the twisted wire102.

In the above description, the production is performed in this order ofthe “process of hanging the middles of the electric wires,” the “processof chucking one ends of the electric wires”, and the “process ofchucking the other ends of the electric wires”. However, for example,the order may be this order of the “process of hanging the middles ofthe electric wires,” the “first electric wire hoisting process,” the“second electric wire hoisting process,” the “process of chucking oneends of the electric wires,” and the “process of chucking the other endsof the electric wires”. The order is also slightly given in thedescription of the process of chucking the other ends of the electricwires, but it may be this order of the “process of hanging the middlesof the electric wires,” the “process of chucking one ends of theelectric wires,” the “process of chucking the other ends of the electricwires,” the “first electric wire hoisting process,” and the “secondelectric wire hoisting process”.

Method of Producing Short Twisted Wire 102 (without Wire LengthDifference)

Next, a method of producing (a producing process of) the short twistedwire 102 will be described. Here, the producing process includes aprocess of hanging the middles of the electric wires, a process ofchucking one ends of the electric wires, an electric wire hoistingprocess (a third electric wire hoisting process), a process of chuckingthe other ends of the electric wires, a tension adding process, anelectric wire twisting process, a taping process, and a removingprocess.

Hereinafter, the processes will be described with reference to FIGS. 19Ato 23B (as well as with reference to FIGS. 1 to 11 as needed).

Process of Hanging the Middles of the Electric Wires

In the process of hanging the middles of the electric wires illustratedin FIGS. 19A and 19B, work of ejecting the two long electric wires 101from, for instance, a part rack (an electric wire stock rack) around aworker, and work of hanging the U turn sections 106 of the two electricwires 101 on the electric wire hanging part 10 are performed.

Process of Chucking One Ends of the Electric Wires

In the process of chucking one ends of the electric wires illustrated inFIG. 20A, work of chucking the one ends 103 of the two electric wires101 with the one end chuck part 42 is performed.

Electric Wire Hoisting Process (Third Electric Wire Hoisting Process)

In the third electric wire hoisting process illustrated in FIG. 20B, thehigh/low-speed elevating unit 8 is operated to raise the position of theelectric wire hanging part 10 from the “initial position” to the“position of the desired hoisting height” slightly above the initialposition at a low speed. With regard to the raising at a low speed, theair pressure switching electromagnetic valve part 28 d is set to a lowair pressure by control (instruction) of the controller main body 52based on short electric wires 101. The raising/lowering switchingelectromagnetic valve part 28 e is set to the raising. When there is,for instance, a button operation of a worker, the slow raising of theelectric wire hanging part 10 is initiated by these parts. That is, thehoisting of the two electric wires 101 is initiated.

Here, with regard to the electric wire hoisting process, setting as the“third” is because the “first” and the “second” are used in theaforementioned method of producing a long twisted wire 102, and there isa need to distinguish from each other to operate differently.

The method of producing a short twisted wire 102 is operated as followswithout using the sensors 30 provided for the elevating guide part 7.That is, when there is, for instance, a button operation of a worker, asignal thereof is sent to the controller main body 52, and the timer isoperated. After the electric wire hanging part 10 is slowly raised for aprescribed time (several seconds), the electric wire hanging part 10 isoperated to be exactly stopped at the position of the desired hoistingheight.

In the controller main body 52, data such as lengths (wire lengths) andraising strokes of the electric wires 101, a timer time, etc. arepreviously stored in a time table in numerous patterns. In the case inwhich the short twisted wire 102 is produced, the timer time isdetermined from the lengths of the electric wires 101, and air of a lowpressure is fed to the elevating cylinder 27 for this timer time. Whenthe electric wire hanging part 10 is slowly raised and stopped at thedetermined time, the electric wire hanging part 10 exactly comes at theposition of the desired hoisting height.

Process of Chucking the Other Ends of the Electric Wires

In the process of chucking the other ends of the electric wiresillustrated in FIG. 20C, work of chucking the other ends 104 of the twoelectric wires 101 with the other end chuck part 43 is performed (seeFIG. 24 with regard to a state in which the electric wires are chucked).

Tension Adding Process

In FIG. 20C, when the position of the electric wire hanging part 10 israised to the “position of the desired hoisting height,” a “restoringforce” generated by downward contraction of the tension adding part 12is applied to the two electric wires 101 at this time. That is,excessive tension is applied.

Electric Wire Twisting Process

In the electric wire twisting process illustrated in FIG. 21A, first tosixth processes below are performed in turn.

First, in a first process, the other end chuck part 43 is rotated, forinstance, in a direction of an arrow by the left same-direction rotatingpart 44. Next, in a second process, as illustrated in FIG. 21B, theother end chuck part 43 is rotated only several times in the oppositedirection of the above, and untwisting is performed. The twisted section107 is formed at the left side of the electric wire hanging part 10 bythese two processes. Next, in a third process, the chuck-verticalposition changing unit 45 is operated to slightly change the positionsof the electric wire hanging part 10 and the one end chuck part 42 in adownward direction as illustrated in FIG. 21C. At this time, thepositions of the U turn sections 106 hung on the electric wire hangingpart 10 are displaced. In other words, a position of the untwistedsection 109 is displaced in a clockwise direction.

Next, in a fourth process, as illustrated in FIG. 22A, the one end chuckpart 42 is rotated in a direction of an arrow by the rightsame-direction rotating part 44. Next, in a fifth process, asillustrated in FIG. 22B, the one end chuck part 42 is rotated onlyseveral times in the opposite direction of the above, and untwisting isperformed. The twisted section 107 is also formed at the right side ofthe electric wire hanging part 10 by these two processes. Finally, in asixth process, the positions of the electric wire hanging part 10 andthe one end chuck part 42 which are changed in a downward direction arerestored as illustrated in FIG. 22C. Due to this process, the twistedsection 107 is disposed at both sides of the electric wire hanging part10 at a uniform length.

Taping Process

In the process illustrated in FIG. 23A, work for taping TP is performed.The taping TP is formed at ends of the twisted section 107 around theone end chuck part 42 and the other end chuck part 43. The taping TP iscarried out for anti-fraying.

Removing Process

In the removing process illustrated in FIG. 23B, the high/low-speedelevating unit 8 is operated to return the position of the electric wirehanging part 10 from the “position of the desired hoisting height” tothe “initial position.” Work of removing one end 103 and the other end104 of the twisted wire 102 from the one end chuck part 42 and the otherend chuck part 43 is also performed. The sequential production iscompleted by the removal of the twisted wire 102.

Method of Producing Twisted Wire 102 (with Wire Length Difference)

Next, a method (a producing process) in which the long or short twistedwire 102 is produced or the wire length difference ΔL (see FIGS. 3A and3B) occurs at the two electric wires 101 will be described. Here, thismethod is different from the method aforementioned with reference toFIGS. 12A to 23B in that a wire length difference absorbing processfunctions.

Process of Chucking the Other Ends of the Electric Wires

In the process of chucking the other ends of the electric wiresillustrated in FIG. 24, work of chucking the other ends 104 of the twoelectric wires 101 with the other end chuck part 43 is performed. Atthis time, the other ends 104 of the two electric wires 101 becomes astate as illustrated in the drawing. That is, the two terminal fittings108 are disposed at the same position by the terminal contact part 62,and the two electric wires 101 become a state in which they are tuckedand held in the chuck main body 63 in the vicinity of the two terminalfittings 108. The two electric wires 101 become a state in which theyare stuck between the twist prevention parts 65 (the pair of pinsarranged side by side), and the inter-electric wire inserting part 68becomes a state in which it is stuck between the electric wires of thetwo electric wires 101.

Tension Adding Process

In the tension adding process illustrated in FIG. 25, tension isautomatically added to the other ends 104 of the two electric wires 101.To be specific, when the position of the electric wire hanging part 10is raised to the “second prescribed position (position of the desiredhoisting height” (see FIG. 14B), the tension adding part 12 (see FIG. 5)is contracted downward at this time, and thus a “restoring force” of thetension adding part 12 is automatically applied (naturally applied) tothe two electric wires 101.

Wire Length Difference Absorbing Process

In the wire length difference absorbing process illustrated in FIG. 25,the wire length difference ΔL (see FIGS. 3A and 3B) occurring at the twoelectric wires 101 is automatically absorbed. To be specific, when the“restoring force” of the tension adding part 12 is applied to the twoelectric wires 101, the short electric wire 101 becomes a state in whichit is spread straight as illustrated in the drawing due to the wirelength difference ΔL. At this time, the short electric wire 101 pressesthe inter-electric wire inserting part 68, and thus the long electricwire 101 becomes a state in which it is bent in an approximate “<” shapebetween the chuck main body 63 and the twist prevention parts 65 alongwith the movement of the inter-electric wire inserting part 68. Sincethe bent portion of the approximate “<” shape is formed, the longelectric wire 101 becomes a state in which it is spread straight at aposition above the twist prevention parts 65. Accordingly, in the wirelength difference absorbing process, the wire length difference ΔL isautomatically absorbed (naturally absorbed).

When the wire length difference ΔL is absorbed, subsequent formation ofthe twisted section 107 (see FIG. 26) naturally has reliability (sincethe twisted section 107 is not formed in an uneven state, it hasreliability. In other words, since accuracy of the twist pitch is notlowered, the twisted section has reliability.).

As illustrated in FIG. 27, the wire length difference absorbing part 66is also provided for the one end chuck part 42, and thereby the wirelength difference absorbing process is performed at both end sides ofthe wire length difference absorbing part. In this case, the absorptionof the wire length difference ΔL is naturally variable.

Effects of Twisted Wire Producing Apparatus 1 and Method of Producingthe Same

As described above with reference to FIG. 1 to FIG. 27, according to thetwisted wire producing apparatus 1 and the method of producing the same,although the variation (the wire length difference ΔL) within thedimensional tolerance within which one of the two electric wires 101 islonger than the other is present at the two electric wires 101, thetwisted wire 102 can be produced while this variation is being absorbedby the wire length difference absorbing part 66 or the like.

As in the present invention, if the wire length difference ΔL can beabsorbed, the state in which the twisted section 107 is formed at thetwisted wire 102 can be stabilized.

According to the twisted wire producing apparatus 1 and the method ofproducing the same, since the wire length difference absorbing part 66is arranged at a position corresponding to the terminal untwistedsection 111 close to the other end of the twisted wire 102, no hindranceis caused in forming the twisted section 107. As a result, the state inwhich the twisted section 107 is formed can be further stabilized.

As can be seen from the above, according to the twisted wire producingapparatus 1 and the method of producing the same, the state in which thetwisted section 107 is formed can be stabilized, and thus quality can beguaranteed without performing measurement or the like of an inter-wiregap and a characteristic impedance. Accordingly, an effect that thetwisted wire producing apparatus 1 and the method of producing the samethat have high reliability of the twisted wire 102 and can contribute toreduction in cost can be provided is exerted.

In addition, according to the twisted wire producing apparatus 1 and themethod of producing the same, the apparatus and the method become anapparatus and a method having a configuration and structure that securea space required to produce the twisted wire 102 in a vertical directionrather than a horizontal direction as in a conventional example, andthus the full length of the apparatus can be significantly shortenedcompared to that of the conventional example.

According to the twisted wire producing apparatus 1 and the method ofproducing the same, the apparatus and the method become an apparatus anda method having a configuration and structure that dispose the one ends103 and the other ends 104 of the two electric wires 101 at positionsclose to each other and produce them. Thus, positions of the ends of thefinished twisted wire 102 are close to each other, and it is unnecessaryto walk to go to the positions of the ends as in the conventionalexample. As a result, a burden of a worker can be dramatically reduced.

Further, according to the twisted wire producing apparatus 1 and themethod of producing the same, the apparatus and the method become anapparatus and a method having a configuration and structure that canchange a speed when the two electric wires 101 are hoisted. Thus, forexample, when the long twisted wire 102 is produced, if the speed is setto a low speed before the position of the desired hoisting height or ifthe speed is set to a low speed from the initial position to theposition of the desired hoisting height, a great tensile force is notabruptly applied to the two electric wires 101. As a result, a troublesuch as damage can be prevented.

Therefore, as can be seen from the above, according to the presentinvention, an effect that the twisted wire producing apparatus 1 and themethod of producing the same capable of promoting a reduction ininstalling space or the like and an improvement in workability andpreventing a great tensile force from being applied to the two electricwires 101 can be provided is exerted.

According to the present invention, the apparatus and the method becomean apparatus and a method having a configuration and structure that hangand hoist the U turn sections 106 made in the middles of the twoelectric wires 101. Thus, the finished state of the twisted wire 102 canbe in an upward U-turned state. As a result, a height of the apparatusbecomes half, and thus an installing space can be further reduced.

In the above description, the sensor 30 (see FIG. 1, corresponding toreference numeral 30 a) approximately in the middle of the elevatingguide part 7 is set to the “first prescribed position.” Further, when itis necessary to produce the long twisted wire 102, for example aposition of the uppermost sensor 30 (to which the reference numeral 30 bcorresponds) of FIG. 1 may be set to the “first prescribed position.”Thereby, although not particularly illustrated, the long twisted wire102 can be produced likewise.

Although the detailed description has been omitted, when the shorttwisted wire 102 is produced, the one ends 103 and the other ends 104 ofthe two electric wires 101 may be chucked, for instance, by the one endchuck part 42 and the right option chuck part 13, and then the one endchuck part 42 may be rotated to perform the twisting. When the wirelength difference ΔL (see FIGS. 3A and 3B) occurs at the two electricwires 101, the other end chuck part 43 may be used.

Naturally, the present invention can be variously modified withoutdeparting from the spirit of the present invention.

The absorption of the wire length difference ΔL as in the presentinvention can also be applied to a laterally long type producingapparatus as in the conventional example.

What is claimed is:
 1. A twisted wire producing apparatus for producinga twisted wire having a twisted section and terminal untwisted sectionseach continuing to corresponding one of sides of the twisted section bytwisting two electric wires, the twisted wire producing apparatuscomprising: an electric wire twisting unit that performs twisting on thetwo electric wires; a controller that controls the electric wiretwisting unit; and a tension adding part that adds tension to the twoelectric wires; wherein the electric wire twisting unit includes a oneend chuck part for chucking one end of each of the two electric wires,an other end chuck part for chucking the other end of each of the twoelectric wires, and chuck rotating parts for rotating the one end chuckpart and/or the other end chuck part under control of the controller,the other end chuck part includes: a base; a chuck main body provided atthe base and configured to fix the other end of each of the two electricwires at prescribed positions; twist prevention parts directly orindirectly provided at the base configured to correspond to a boundaryposition between the twisted section and the terminal untwisted section;and a wire length difference absorbing part directly or indirectlyprovided at the base to absorb a wire length difference occurring at thetwo electric wires, the wire length difference absorbing part includesan inter-electric wire inserting part configured to be stuck betweenelectric wires of the two electric wires, and the inter-electric wireinserting part is provided as a part that is movable in a directionperpendicular to a direction in which the two electric wires extend, andis disposed corresponding to an intermediate position between the twistprevention parts and the chuck main body.
 2. The twisted wire producingapparatus according to claim 1, wherein the inter-electric wireinserting part is formed in a shape of a pin having a circular crosssection and is formed as a replaceable component to match absorptionamount of the wire length difference by replacing the inter-electricwire inserting part with the other inter-electric wire inserting parthaving a different diameter.
 3. The twisted wire producing apparatusaccording to claim 1, wherein the other end chuck part further includesa terminal contact part for bringing tips of terminal fittings providedon the two electric wires into contact with each other at the sameposition.